Pressure gauges of this type generally include a body, a pressure sensor member consisting of an elastically deformable bent tube which is fixed to the said body and has a fixed end for communicating with a fluid with a view to measuring its pressure and a closed opposite end which is free to move relative to the said body under the effect of the pressure of the fluid and controls a pressure indicator.
These pressure gauges have very high precision but include particularly fragile parts, for example the mechanism connecting the Bourdon tube to the needle, the needle and the Bourdon tube.
In order to prevent the pressure gauges from being destroyed when they are subjected to direct impacts, that is to say impacts which are directly applied to them, it is known to equip their casing with an elastomer liner in order to absorb the impacts. Other pressure gauges are equipped with a metal grill forming a cage around the casing.
Protectors of this type give effective protection against direct impacts.
However, protectors of this type are not effective against accelerations in excess of 400 g, for example due to dropping a bottle on which the pressure gauges are fitted.
Indeed, under the effect of its own weight and the weight of the parts which are fixed to it, the Bourdon tube will in this case tend to deform beyond its elastic limit, which causes damage to the pressure gauge.
Furthermore, when it deforms, the tube may crush the needle control mechanism, which makes the pressure gauge unusable.